cfi: Disable simple-pass.cpp on Darwin.
cfi: Disable simple-pass.cpp on Darwin.

-mretpoline does not work yet on Darwin.

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@327168 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt